Phenotypic differentiation of Round goby (Neogobius melanostomus) along small-scale invasion succession

摘要: Biological invasions are a major threat to biodiversity world wide with annual economic costs up 1.4 trillion dollars. The round goby (Neogobius melanostomus) is particularly fierce invader that threatens ecological function of the Baltic Sea. Individual variation in behavioral traits remain constant through time and context have been identified as crucial factors for explaining different parts invasion process. For example, asocial behavior facilitates dispersal from high density populations comes fitness benefits low conspecific density. latter especially relevant, an context, following initial colonization novel environment when population usually low.This thesis investigates role individual phenotypic on species invasions. main focus effects sociability, activity boldness, but also including aggression physiological stress tolerance, tendency selection at fronts. To do this, we studied four Sea, two most recently established oldest populations.In 2012 demonstrated asocial, active bold gobies overrepresented Two years later showed new was led by individuals levels, while all larger dispersed. We determined length socalled lag-phase, between spread, both newly populations. end lag-phase hypothesized being triggered harbors leading subsequen surrounding areas small individuals. In our final experiment, present evidence coping styles gobies, which more aggressive tolerant vice versa. Though found no connection age, mortality unaffected became kept density.To conclude, shown that: 1) levels activity, boldness asociality common fronts; 2) lag phase occurs spread invasions; 3) drive front and; 4) adapt densities tolerance.